A full-spectrum hemp extract was more effective than CBD alone at preventing meth relapse in rats

All CBD-containing treatments reduced meth-primed reinstatement, but hemp extract (HE) and CBD+HE were more effective than CBD isolate alone. The hemp extract contained only 2.5 mg/kg CBD versus 80 mg/kg in the isolate, yet performed better. Neither cannabinoid treatment produced conditioned place preference (no rewarding properties). The 5-HT1A receptor was not involved.

Male Sprague-Dawley rats self-administered methamphetamine via lever press, underwent extinction, then reinstatement by meth injection. Four treatment conditions: vehicle, CBD isolate (80 mg/kg), hemp extract (HE, 2.5 mg/kg CBD + other cannabinoids), or CBD+HE (80 mg/kg total CBD). 5-HT1A antagonist co-administration tested. Conditioned place preference and behavioral sensitization also assessed.

Methamphetamine addiction has no approved pharmacotherapy. This study suggests full-spectrum hemp preparations may be more effective than pure CBD for preventing relapse, potentially at much lower CBD doses, supporting the entourage effect hypothesis in addiction treatment.

The fact that a hemp extract with only 2.5 mg/kg CBD outperformed 80 mg/kg of pure CBD is striking. It suggests that minor cannabinoids or terpenes in the extract contribute meaningfully to anti-relapse effects, with major implications for cannabinoid product development in addiction medicine.

Male rats only. Meth self-administration model may not fully capture human addiction. The hemp extract composition beyond CBD was not fully characterized. The 5-HT1A receptor was ruled out but other mechanisms were not tested.